Whether you ride mountain bikes, DH bikes, or road bikes, brakes are crucial to your safety.
I. Should You Use the Front or Rear Brake for Emergency Stops — The Powerful Role of the Front Brake
Since your bike has two sets of brakes—one for the front wheel and one for the rear—you need to fully understand how to use them to stop safely.
The common advice is: use both the front and rear brakes together. This theory is very useful for beginners who are not yet skilled in riding, but if you never progress beyond this stage, you won’t be able to develop the professional techniques required for expert control of your bike.
Typically, the best way to stop in the shortest distance is to pull the front brake until the rear wheel is just about to lift off the ground. As you move forward, both your body and the bike have forward inertia, combined with the downward force of gravity—these two forces work together to create a resultant force directed forward and downward. The braking action relies on the friction between the tires and the ground to counteract the forward component. The greater the pressure, the greater the friction, so most of this friction comes from the front wheel. Since the rear wheel lifts off, the rear brake has no effect at all. On loose or slippery surfaces, or in the event of a front tire blowout, you should make full use of the rear brake. However, on normal dry and flat roads, both theoretically and practically, the front brake always provides the greatest braking power. Once you learn to properly use the front brake, you’ll become a safer rider.
You might worry that doing this will cause you to flip over the handlebars. It’s possible, but only for those who haven’t yet mastered controlling the force of the front brake. For riders who rely solely on the rear brake to stop, they often realize after an accident that, in a panic, they instinctively grab the unfamiliar front brake and increase braking force along with it—resulting in a forward somersault, which can lead to injury.
Some also believe that “forward somersaults” aren’t caused by too much front brake force, but rather by using the front brake forcefully without using arm strength to counteract the deceleration. The bike stops, but the rider continues moving forward until their hips “sit” on the handlebars, and the bike ends up “riding” the person. This doesn’t happen to those who only use the rear brake because when the rear wheel lifts off the ground, it loses friction and thus braking power—but the trade-off is that the stopping distance is twice as long as when using the front brake. Therefore, for riders who frequently ride at high speeds, relying solely on the rear brake is unsafe. Remember, during emergency braking, use your arms to firmly support your body and prevent flipping forward. The key is to push your hips back as far as possible (don’t stay glued to the saddle) and shift your center of gravity backward as much as you can. This technique applies to all braking conditions, whether you’re using just the front brake or both the front and rear brakes.
Using both the front and rear brakes simultaneously can easily cause “fishtailing.” If the rear wheel begins to slide while the front brake is still applied, it can cause the rear wheel to swing past the front wheel, because the deceleration force of the front wheel is greater than that of the rear wheel. Once the rear wheel begins to slide, it tends to skid sideways rather than forward. In such cases, you must immediately reduce the rear brake force or fully release the rear brake to restore the rear wheel’s normal trajectory.
In summer, on hot asphalt or concrete roads, the front brake is used more often than the rear—arguably the front brake takes the lead, the rear plays a supporting role, or you may not even need the rear brake at all. Some people abroad strongly advocate for this approach.
Theoretically, the maximum braking effect occurs when the front brake is applied until the rear wheel is just about to lift off the ground. At this point, even a slight additional force on the rear brake can cause it to slide. To experience this theory, find a large open area, apply both the front and rear brakes, but put most of the force on the front brake, and keep pedaling. Your feet will feel the rear wheel lifting. Start by slowly accelerating to get a feel for it, then gradually increase speed and practice emergency braking until you notice this phenomenon. This way, you’ll learn to judge the critical point where the rear wheel is just about to lift.
II. The Great Role of the Rear Brake
If the front brake alone is enough, then what’s the point of the rear brake? Actually, the rear brake still has significant uses and is essential in certain situations.
1. Slippery Surfaces: On dry roads, tires rarely slip, but on slippery surfaces, the situation changes. In such conditions, if the rear wheel slips, it’s relatively easy to regain balance. But if the front wheel slips, recovery is nearly impossible—so you must use the rear brake to stop the bike.
2. Loose Surfaces: The situation is similar to slippery surfaces. The likelihood of tire slippage increases significantly, so you must also use the rear brake to stop the bike. You may cautiously use the front brake here, but only to the extent that the front wheel doesn’t slip.
3. Bumpy Surfaces: When riding on bumpy terrain, wheels may leave the ground. In such cases, do not use the front brake. If you apply the front brake while the front wheel is off the ground, it will lock up—and landing on a locked front wheel is a very bad scenario.
4. Front Tire Blowout: If your front tire blows out while riding, do not use the front brake. Applying the front brake in this case may cause the tire to come off the rim, potentially leading to the bike flipping over.
5. Front Brake Failure: If the front brake cable breaks, the brake pads are excessively worn, or any other issue renders the front brake unusable, you’ll have no choice but to use the rear brake.
III. Which Side of the Handlebar Should the Front Brake Lever Be Installed On
Another question is: should you use your right or left hand to control the front brake? There’s actually quite a bit of debate over which side of the handlebar the front brake lever should be installed on. Some riders argue that it’s best to use your strongest hand (the right hand for right-handed people) to control the rear brake. Motorcycle riders have always used their right hand for the front brake, so those who are both motorcyclists and cyclists often adopt the same setup to avoid confusion.
In countries where people drive on the right, the front brake lever is commonly installed on the left side of the handlebar; in countries where people drive on the left, the front brake is also generally installed on the left side of the handlebar. The reason is that one hand is needed for signaling while the other can still control the bike. The hand that remains on the handlebar is usually used to control the rear brake, because single-handed braking is more stable with the rear brake—and braking distance is less critical in everyday riding compared to racing, since you rarely ride at high speeds. The United States has even legislated that all bicycles must have the front brake lever installed on the left side of the handlebar (CPSC standard) from the factory. Once this becomes a habit, you’ll instinctively grab the correct lever in emergencies, avoiding accidents.
In reality, which side the brake lever is installed on isn’t the deciding factor. What’s important is that you know how to use both the front and rear brakes and can skillfully control them. Both hands can be trained to become adept—if you get used to a certain setup, don’t change it arbitrarily. Otherwise, thinking about which lever controls which wheel during an emergency would be terrible. When arranging left and right brakes, there’s also a secondary factor to consider: whether the cable guides on the frame and the routing of the brake cables are smooth. Although both sides can be used, if the routing isn’t smooth, it can affect brake operation and the reliability of the brake cables. A more common issue is surface wear on the frame caused by the brake cables.
IV. Body Position and Brake Control When Cornering
Let’s talk about how to lean your body when turning. As everyone knows, according to the laws of circular motion, you must lean inward when turning. The faster you go, the greater the angle of lean required. Centripetal force and centrifugal force must balance; otherwise, you’ll fall. This is a physical phenomenon no one can change. So is there nothing more to discuss? Not necessarily. Maybe you’ve ridden motorcycles (or at least seen them!). GP road racers lean their bodies at a greater angle than the motorcycle when turning—this allows the bike to take the corner at a more upright angle relative to the ground, increasing tire grip. Take a look at the posture of those racers—every single one does this. So should cyclists do the same? Well, motocross riders do the opposite—their body lean angle is almost always less than the bike’s, especially during high-speed turns. The rear wheel may slide, and this posture keeps the rider above the bike, allowing them to control the center of gravity and maneuver the bike flexibly. Doing the opposite will definitely frustrate you. By now, you might be confused—what’s the right approach? My view is to keep your body’s center of gravity aligned with the bike’s center of gravity on the extended plane of the frame. For road bikes, since cycling speeds aren’t as high as in GP racing, it’s not necessary to overcomplicate things. At normal speeds and corner angles, just make sure your body lean angle is slightly greater than or equal to the bike’s lean angle. Just be careful not to hit the inner pedal on the ground while turning.
For cross-country or downhill mountain bikes, this is also the most stable riding posture for controlling the bike. Don’t believe it? Try shifting your body weight onto one foot and deliberately leaning your body at a different angle than the bike’s on rough terrain—feel how the bike moves. Isn’t it quite wild? On the same stretch of road, if you keep your body’s center of gravity aligned with the bike’s on the extended plane of the frame, you can even ride hands-free. However, when taking tight hairpin turns at high speed, both road and mountain bikes can mimic off-road motorbike techniques by leaning your body at a smaller angle than the bike’s. This allows you to react quickly and maintain balance if the rear wheel slides. Remember: do not use the front brake in these situations.
V. Conclusion
Back to basics. Many people think using the front brake while turning is very dangerous. If your riding posture and cornering technique are incorrect, then this is indeed true. As mentioned earlier, you must shift your center of gravity inward to maintain balance during turns. We’ve also discussed three cornering postures, but typically only one is correct—that is, keeping your body’s center of gravity on the extended plane of the frame. This is the most stable posture. When your body lean angle differs from the bike’s, your body exerts lateral stress on the bike. Using the front brake in this state will cause centrifugal force to throw you toward the tangent line—and a crash is often the result. To experience this force, try riding straight on a bumpy road, shift your body weight onto one foot, tilt the bike, and gently pull the front brake lever. Pretty scary, right?
Purely in terms of braking performance, relying on the front brake alone should be fine, but the stress on the fork is extremely high. If you’re using a long-travel, highly elastic front fork (such as the Rock Shox Judy XL), you can observe how much it bends backward when using only the front brake — it’s honestly quite painful to watch. This lateral stress is a significant test for the fork. Under such conditions, internal damping increases dramatically, and some lower-end suspension forks may not even compress. However, if you use the rear brake as well to share the braking force, the degree of fork bending is greatly reduced. So, in my humble opinion, the ideal braking habit is to make flexible use of both the front and rear brakes. On regular roads, where there’s no concern about the front wheel skidding, prioritize the front brake with the rear as support. In situations that could cause the front wheel to skid, prioritize the rear brake with the front as support. If you’re worried that switching between the two might be confusing, consider the following approach: road cyclists or those who ride mostly on paved roads should primarily use the front brake with the rear as backup; whereas riders who enjoy off-road riding or even love downhill activities should primarily use the rear brake with the front as backup, which would be more appropriate.